ProvideX V8.20 > Language Reference > 2. Directives

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If you do not specify size, the default is VLR with a maximum record size

of 256. The maximum block size for a VLR file is 31KB and the maximum

record size is 31000 bytes. Attempting to create a VLR file with a record size

more than 31000 bytes results in an FLR file with the requested record size.

Supported file options (see also, File Options, p.808):

fileopt

BSZ=num Block size. Numeric expression (1 - 63).

ERR=stmtref Error transfer.

SEP=char$ Default field separator character. Hex or ASCII string value.

OPT=char$ Single character settings:

"C" - Compressed. Adds simple compression to record data.

"X" - Extended Record Size. Extends record sizes up to 2GB per record.

"0" - Create VLR/FLR files (default if 'KF'=0)

"1" - Create EFF Files with 2GB limit.

"2" - Create EFF Files without 2GB limit (supported platforms).

"Z" - Set ZLib Compression for VLR and EFF Files.

Note: OPT="2" generates Error #99: Feature not supported

on platforms that do not offer Large File Support (LFS). Using options

"Z" and "C" together will result in an Error #32.

Description

Use the CREATE TABLE directive to create a file with one or more keys. If the first

field in the directive after the filename is a number, ProvideX creates an external file

key (i.e., an index to the file). If the first field in the directive is a key definition

enclosed in square brackets [ ], then ProvideX uses only internal key fields instead.

Note: By default, the CREATE TABLE directive will create Enhanced File Format (EFF)

files on platforms that support Large File System (LFS), 64-bit addressing; however,

by setting OPT="0" in the syntax, CREATE TABLE can also be used to create

variable-length record (VLR) data files or fixed-length record (FLR) formatted files. For

more information on VLR/FLR, refer to the KEYED Directive, p.165.

ProvideX considers the first key specified for an EFF file to be the primary key. Every

record must have a unique primary key. You can have duplicate secondary keys

from record to record. There is a maximum of 255 keys allowed on a file with a

maximum of 255 data components making up these 255 keys. For VLR/FLR files,

there is a maximum of 16 key fields allowed on a file with a maximum of 96 data

components making up the 16 keys. There is no limit (other that the maximum of 96

key components) to the number of fields that comprise a key. The initial

implementation of EFF (in Version 6) is limited to 96 keys and 96 segments.

If a given filename already exists, ProvideX returns Error #12: File does not

exist (or already exists).

Keys have the following limits:

· Maximum external key size is 127 bytes.

· Maximum internal or alternate key size is 240 bytes.

· Maximum segment size is 127 bytes.